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US Department of Energy: Fusion Ignition Achieved

energy.gov

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Re: US Department of Energy: Fusion Ignition Achieved

#411

Post by ceejayoz »

eitland wrote: post #392
Firmwarrior wrote: post #293

Earlier quoted context omitted.

Let's take a step back and remember something: If Russia and the USA had a "war" it would consist of reducing each other to the Stone Age in a couple of hours, then struggling not to starve to death

Why do you think a country that isn't capable of properly maintaining tanks is capable of maintaining nukes? I mean, ICBMs are literally rocket science with nuclear physics on top of them. How can a country that cannot even prevent theft of electronics from their "doomsday plane" in front of the 9th of May parade keep a fleet of ICBMs operative? In a normal year Russia has a total military budget that is smaller than…

A nuclear arsenal where only 100 of the 6,000 warheads are actually maintained and functional is still a useful one, though. Less so if 100/6,000 tanks work.

Re: US Department of Energy: Fusion Ignition Achieved

#412

Post by saboot »

makestuff wrote: post #353
jkelleyrtp wrote: post #33

> LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE) Yesterday, everyone was complaining about the 2.2:2.0 ratio, but now we're working with 3.15:2.05. With modern lasers, that'd be a total Q of 0.375 assuming 100% ef…

> It's nice to see this milestone recognized, even if the funding it still rather small. Just wait until the DoD figures out they can use this for some military application and it will get 100x funding overnight.

The appropriate analogy for this technology would be that it may be possible to initiate a thermonuclear weapon without relying on fission at all. Currently we use a fission nuclear bomb just to generate the temperature and pressure needed to start the fusion reaction, same as the one on today's announcement.

So far it hasn't proven to be viable, but time will tell.

Re: US Department of Energy: Fusion Ignition Achieved

#413

Post by saboot »

davrosthedalek wrote: post #407
p_j_w wrote: post #366

Earlier quoted context omitted.

This is already used for nuclear weapons research, which is why it's under Dept. of Energy.

Not really. I mean, yes, nuclear weapons are a thing, but Dept. of Energy supports many many directions not related to nuclear weapons. Physics research is mostly funded by DOE Office of Science or the National Science Foundation.

It's an explicit goal of the NIF to better understand the physics of fusion for weapons research. Not the main one but it's pretty important!

Re: US Department of Energy: Fusion Ignition Achieved

#414

Post by 29athrowaway »

eklitzke wrote: post #262
spullara wrote: post #165

Earlier quoted context omitted.

If you look at the mass before of their fuel, 1 deuterium atom + 1 tritium atom: 2.01410177811 u + 3.01604928 u = 5.03015105811 u vs the mass of the fusion products of 1 helium atom and 1 neutron: 4.002602 u + 1.008 u = 5.010602 u You'll notice that even though we started with 5 neutrons and 2 protons and ended up with the same number there was some additional binding energy that is unaccounted for in the new configu…

Tangentially related, but I think this is an interesting fact, all the atoms in our universe/galaxy/solar system with a mass up to that of iron are formed in the core of stars in stellar fusion. Hydrogen fuses into helium, and as a star nears the end of its lifetime you get heavier elements like lithium, carbon, and so on. Under normal stellar fusion no elements heavier than iron will be produced, and iron is only el…

It is also interesting that the Milky Way will collide with Andromeda and then we will be invaded by zerg.

Re: US Department of Energy: Fusion Ignition Achieved

#415

Post by petilon »

whimsicalism wrote: post #395
petilon wrote: post #349

Earlier quoted context omitted.

When you consider that they laser they used consumed 300 megajoules from the wall plug, in order to send 1.8 megajoules to the target, the fact that they got 2.5 megajoules out looks puny in comparison. Even newer lasers only have 20% wall plug efficiency according to the press conference. So the important point here is, there was no net energy gain. They spent 300 megajoules to get 2.5 out. The scientists only talk…

Energy is conserved in the universe so there is never any net energy gain. See how pedantic and not helpful that is?

In nuclear fusion, mass is converted into energy according to the famous equation E = mc^2, where E is energy, m is mass, and c is the speed of light.

Re: US Department of Energy: Fusion Ignition Achieved

#416

Post by kortilla »

p_j_w wrote: post #366
makestuff wrote: post #353

Earlier quoted context omitted.

> It's nice to see this milestone recognized, even if the funding it still rather small. Just wait until the DoD figures out they can use this for some military application and it will get 100x funding overnight.

This is already used for nuclear weapons research, which is why it's under Dept. of Energy.

That doesn’t follow. The DOE covers a bunch of energy research that has no relationship to nuclear weapons (e.g. solar).

Re: US Department of Energy: Fusion Ignition Achieved

#417

Post by alasdair_ »

freediver wrote: post #38
puttycat wrote: post #25

2022, not ordered by importance: Dall.E 2, Chat-GPT, Fusion Ignition. Can't wait for 2023.

Putting these in the same basket is hardly justified.

True. AI will have a much bigger impact on humanity in the next two decades than fusion will.

Re: US Department of Energy: Fusion Ignition Achieved

#418

Post by mustacheemperor »

Firmwarrior wrote: post #293
ceejayoz wrote: post #265

Earlier quoted context omitted.

> Uh what US warfare have you been watching? Russia is struggling with Ukraine and the NATO weaponry they've been gifted. 100 mile supply lines proved too much, and they failed entirely to achieve air superiority. There's zero reason to think they'd do better against the US more directly.

Let's take a step back and remember something: If Russia and the USA had a "war" it would consist of reducing each other to the Stone Age in a couple of hours, then struggling not to starve to death

Let's check our assumptions. The bulletin of atomic scientists first published in 2017 [0] that they felt the modernized US nuclear arsenal is likely sufficient to execute a devastatingly successful first-strike against the Russian arsenal and nuclear command and control, because the new 'super-fuze' in the submarine arsenal significantly upgrades the hard-target kill capability of the warheads. The risk they communicate in this article is that Russia will misinterpret a false positive from their early warning system (which offers only half the warning time of the US') and launch a "retaliatory" strike against the US on a false alarm, because they do not expect to have that capability after a US strike. The modernization program has continued since 2017 and extended to the minuteman arsenal.

[0] https://thebulletin.org/2017/03/how-us-nuclear-force-moderni...

>the United States would be able to target huge portions of its nuclear force against non-hardened targets, the destruction of which would be crucial to a “successful” first strike...The garrisons and their support facilities would probably be destroyed quickly, and some of the dispersed road-mobile launchers would also be quickly destroyed as they were in the process of dispersing. To destroy or expose the remaining launchers...Just 125 US Minuteman III warheads could set fire to some 8,000 square miles of forest area where the road-mobile missiles are most likely to be deployed. This would be the equivalent of a circular area with a diameter of 100 miles.

>Many of the nearly 300 remaining deployed W76 warheads could be used to attack all command posts associated with Russian ICBMs.

Re: US Department of Energy: Fusion Ignition Achieved

#419

Post by smegger001 »

trhr wrote: post #368
adventured wrote: post #278

Earlier quoted context omitted.

> Uh what US warfare have you been watching? The one where the US tends to perform well against its adversaries. True in the Civil War. True in WW1. True in WW2. True in Korea. True in Vietnam. True in the Gulf War. True in Afghanistan. True in Iraq. And now just a smidgen of its old weapons are helping Ukraine humiliate Russia. The US was in Afghanistan for two decades with 1,932 soldiers killed by hostile action. R…

Quoted post unavailable.

> True in the Civil War.

>You think so? Ya'll lost 200,000 men to Southern fever, steel, and shot. Next time it'll be 20 million. Know your limits, yankee, and stay north of Dallas.

The south started with a treasonous surprise attack and had most of the the infantry that wasn't stationed in isolated western frontier territory or along the us-canada border, the countries war college at westpoint and many of the countries highest generals, once the north got its act together it started to burn the south to the ground. There is a reason the south still dreads the name Sherman.

You got set on fire once when you started the fight with sucker punch, and you want to try to pick fight again?

Re: US Department of Energy: Fusion Ignition Achieved

#420

Post by kortilla »

CuriousCosmic wrote: post #344
azinman2 wrote: post #204

Earlier quoted context omitted.

Is the bottleneck for fusion money though?

yes. fusion funding has been sliding downwards for decades which is a large reason why it takes so long to do anything. It's largely the same reason why NASA takes so long to do anything. 1. Shortage of funding 2. failure can result in loss/exhaustion of funding 3. extremely low risk tolerance 4. physical experiments needing new HW only happen when the likelihood of success is extremely high 5. projects are over engi…

It has nothing to do with funding. SpaceX had far less than NASA.

For another example from a different angle, the military has limitless supplies of funding but innovates even less than NASA.

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